I've got a 71 Charger R/T (440 HP).  I think that it has an overheating problem because the temp gage goes over to the right all the way to the first line marker.  I've replaced the radiator, water pump, thermostat, fan clutch, temp sensor, and radiator cap.  I don't know if the gage is accurate as it is the original.  I'd like to eliminate the temp gage as the problem with an after market gage but use the existing sending unit (a short term solution).  Which brand gage will work with my existing sending unit?
Also, if it isn't the gage, where do I look next?
Thanks  

Sunpro temp gages use the same sending unit.Is your radiator large enough for the big block because they hold alot of water and do you have a shroud. Shrouds are a must.  

HEY I'M LOOKIN FOR SOME FACTS ON THE 71 CHARGER , I'M TRYING TO FIND OUT HOW MANY RT'S WERE MAID WITH A MOON ROOF

THANX